Theatre Room, Meditation Room, All Encompassing Room!

The county requires this treehouse to be 735sqft, but we would really like to keep the treehouse smaller.  Through our travels and treehouse research we have realized a few things:

1. We love running wild in the outdoors and feeling one with nature
2. We defiantly appreciate modern amenities and technology

With that in mind, the treehouse will have indoor/outdoor living areas, it will keep the quaint space of a treehouse but additionally have a feel of a boutique/high end space with modern amenities and technology.   Lot's of wheels are constantly turning ;)

So how do we keep the treehouse smaller than 735sqft and stay on the good side with the county? I have proposed the idea of having an exterior staircase to another structure that would add to the 735sqft.  This idea seems to have been given the go and we are designing with this idea in mind!  Now we have the main structure as well as a 2nd structure.  The main structure will contain a loft, a bedroom, kitchen, lounge area, and balcony.  And what about the 2nd structure?

Exterior Stairs to Secondary Structure and yes we're looking good on this being allowed ;)

What will the 2nd Structure Be?
My husband being the techy nerd that he is has a theatre room in mind. (sounds great)  I  also have in mind a fort type space for quiet meditation (for when the outdoor elements don't allow us to be outside)  Combining these ideas, being open to new ideas, still not quite sure what this 2nd structure will be, but we're having fun creating it :)

Possible Meditative Space in 2nd Structure (for when it's snowing or raining outside)